 Autonomous Underwater Vehicle
Information and Data was submitted to Parallax by Theron Wierenga of Muskegon Public Schools in Michigan:
This autonomous underwater vehicle (AUV) was developed for underwater exploration. Muskegon is on Lake Michigan and there is a large inland lake and harbor with a channel to Lake Michigan. The concept is to develop capabilities for amateur underwater archaeology. Muskegon had many sawmills along the lake 150 years ago.
 There is one large seal that must be watertight. The two main body pieces have a male and female 6 inch PVC adopter which thread together. I anticipated this would leak because the threads are so large. However, it worked quite well when we wrapped the threads with about 10 turns of Teflon tape. The pipe is made to hold water in and it works as well to keep it out. It appears the Teflon will hold for several lock downs and will then be replaced.
The AUV is controlled by a BASIC Stamp® 2 module on a printed circuit board (OEM approach). The BS2 acts as a smart controller for four water pumps for propulsion, a gear motor for pitch control, and a video camera. In addition a pressure gauge for depth readout and metal detector will be added in future days.
 There are many examples of BASIC Stamp computers used in wheeled or tracked vehicles, I have not found anything on the web describing use in an underwater vehicle. The low eight bits of the BS2 drive two L293D circuits which are attached to four small bi-directional pumps for propulsion. Depending on which pumps are turned on and their direction of flow, the nozzles can move the AUV forward, reverse left, right, and pitch up or down. You can download my BS2 source code for this project as well as the AUV Windows control interface I assembled with Visual BASIC for this project.
The tether wire is connected to the serial port of a Windows based computer, which is running a program which send commands to the AUV for the BS2 to receive and execute. In addition this cable returns the video signal. The BS2 works very nicely in this application. It has enough power to receive commands from a serial port and output signals to easily interfaced motor control circuits. |